|Publication number||US4672790 A|
|Application number||US 06/786,732|
|Publication date||Jun 16, 1987|
|Filing date||Oct 11, 1985|
|Priority date||Mar 10, 1982|
|Publication number||06786732, 786732, US 4672790 A, US 4672790A, US-A-4672790, US4672790 A, US4672790A|
|Original Assignee||Bennie Freiborg|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (28), Referenced by (29), Classifications (8), Legal Events (3)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This is a continuation of application Ser. No. 356,937, filed Mar. 10, 1982, now abandoned.
The present invention relates to the field of roofing, and more particularly, non-metallic roofing such as asphalt composition.
2. Prior Art
Asphalt composition roofing materials are very well known in the prior art. These materials are relatively inexpensive and of light weight, thereby finding wide usage. Asphalt composition materials have been folded for various purposes, such as providing improved sealing characteristics and providing areas of increased thickness which create a three-dimensional appearance. Such folding is limited, with the resulting roof again having a highly repetitive design, lacking depth and texture as is generally characteristic of asphalt composition roofs. Examples of such folding may be found in U.S. Pat. Nos. 1,410,299; 1,435,623; 1,596,272; 1,848,965; 1,975,986; 2,253,753; and 3,913,294. In recent years, to enhance the appearance of asphalt composition roofs, various techniques have been used, including varying the thicknesses of the asphalt layer on the base material to provide texture, and use of different color granules on the lower portion of the shingle to provide a shading effect to create an illusion of a deeper three-dimensional roof. In general, the folding of the asphalt composition was difficult and cumbersome and often caused cracking about the folding line.
An asphalt composition roof covering system for roofing and reroofing is comprised of a base and a plurality of tabs cut from standard rolls of asphalt composition material. The base has first, second and third regions separated by a first and second fold so as to provide a "Z" shape. The plurality of folded tabs are inserted into the third region of the base to give a three-dimensional appearance. In addition, when the system is used for reroofing over existing shake roofs, a spacer may be provided along the inclined plane of a shake for raising the base to create a more natural looking appearance, or an alternate embodiment system, also disclosed, may be used.
FIG. 1 is a top plan view of a sheet or portion of a roll of asphalt composition material from which a base of the roof covering system of the present invention is formed.
FIG. 2 is a botom plan view of the sheet of FIG. 1.
FIG. 3 is a detailed cross-sectional view of a folded base.
FIG. 4 is a cross-section of an alternate embodiment base in which there is a single fold.
FIG. 5 is a top plan view of a sheet of asphalt composition material from which the tabs of the roof covering system are formed.
FIG. 6 is a cross-sectional view of a folded tab.
FIG. 7 is a perspective view of the roof covering system in accordance with the present invention.
FIG. 8 is a sectional view of a roof covered by the roof covering system of the invention.
FIG. 9 illustrates the application of the roof covering system of FIG. 7 to reroofing over a wood shake roof.
FIG. 10 illustrates the application of an alternate embodiment roof covering system for reroofing over a wood shake roof.
FIGS. 11 and 12 illustrate the folding and installation of bases alone to provide a low cost roof covering system.
Referring first to FIGS. 1 and 2, illustrating a typical base in accordance with the invention, a sheet 10 of asphalt composition roofing material such as a substrate of asphalt saturated felt has an upper granular surface 12 (shown in FIG. 1) and a lower smooth surface 11 (shown in FIG. 2). A center cut line 18 divides sheet 10 into first and second bases, each half being a mirror image of the other about line 18. The top surface 12 of base 20 scored (scraped or creased) to provide a fold line 24, i.e., a line of reduced resistance to bending, dividing surface 12 into first portion 13 and second portion 15. Adjacent to one side of line 24 is an adhesive strip 22. Adjacent to the other side of fold line 24 is an area 26 which is left free of granules, preferably by applying a strip 31 of plastic tape to the substrate prior to the application of the granules which will not stick to the plastic. Tape 31 which is affixed to surface 12 also serves as a hinge member along line 30, preferably defined by a crease in the bottom surface of the substrate (see FIG. 2), and provides additional structural support by holding the second portion 15 and third portion 17 together.
On the lower surface 11 directly below the line 24 is another strip 25 of plastic tape affixed thereto. The strip 25 which is affixed to surface 11 functions as a hinge member along fold line 24. Strip 25 serves to hold the first portion 13 and second portion 15 together in the event that the asphalt material cracks along the line 24 when subsequently folded. Also, strip 25 serves to prevent moisture from penetrating the exposed fold. The crease defining fold line 30 is directly underneath plastic tape 31, though not symmetrical therewith, and separates second portion 13 from third portion 17.
In the best mode of the invention the inner edge of the strip of adhesive 22 is approximately 3 to 31/2 inches from the center cut line 18. Fold 24 is provided 4 7/16 inches from the center cut line 18. Granule free area 26 is approximately 23/4 inches wide, starting approximately 5 3/16 inches from center cut line 18. Score line 30 is located within area 26, about 7 3/l6 inches from the center line 18 on surface 11. These measurements are based on using asphalt composition material that is one meter wide, and of course are exemplary of the preferred embodiment only. Preferably the bases are cut from rolls or continuous sheets of material so as to have a length in the range of 36 to 40 inches.
Base 20 comprises only one part of the roof covering system of the present invention. Additional parts, referred to herein as tabs 40, about to be described, are integrated with the base during installation and complete the roof covering system.
In FIG. 5, a second sheet 39 of asphalt composition material is partitioned to form tabs 40 above and below center cut line 48 having an upper granular surface 41 and a lower smooth surface (not shown). The ends of each tab 40 are left free of granules in regions 51 and 53. Each tab 40 is creased on the granular side 41 to provide a fold line 52 dividing the tab 40 into first portion 45 and second portion 47. On the lower side and aligned below folding line 52 is a strip of plastic tape 54. On surface 41 of each tab 40 is a strip 56 of adhesive material, normally covered by an overlying plastic tape 58 or some other suitable covering for protection from units sticking together during storage and shipment.
During installation, as shall be described in greater detail hereafter, base 20 is folded about the two fold lines 24 and 30 as shown in FIG. 3. This figure illustrates the approximate relative proportions of the base in the region of each of the two folds. In particular, the substrate of a typical asphalt composition roofing material is approximately one-half the thickness of the final material after application of the asphalt and granule layers. Thus in the region of tape 31 on each side of fold line 30, the asphalt composition material as a thickness of only approximately one-half that of other regions of the material having the granules thereon. Note further that the tape 31 is not positioned symmetrically with respect to the fold line 30, but rather is substantially unsymmetrical with respect thereto. Consequently, for the foregoing reasons, the effective thickness in the region of the fold around fold line 30 is approximately that of the normal asphalt composition material with granules, being comprised of two substrate layers, each having approximately one-half of that thickness. Moving away from the fold line 30, the thickness then increases to approximately three-halves of the thickness of the normal material with granules thereon as a result of the granules on the portion 17 of the base. Finally, going still closer to the fold line 24 and totally out of the region of the plastic tape 31, the thickness as a result of fold 30 further increases to the equivalent of twice the thickness of the basic material with granules thereon. Thus, the net result of the combination of the fold along line 30 and the absence of granules in an unsymmetrical pattern about the fold line is a very definite tapering of the thickness resulting from the fold, tapering from a minimum value in the region of the fold line 30 to a maximum value adjacent fold line 24. Obviously the same taper effect could be achieved by placing the plastic tape in a nonsymmetrical pattern in the opposite direction. In any event, the advantage of the taper is that portion 13 is elevated quite substantially in the region of the fold line 24, though the taper as hereinbefore described minimizes the step in portion 13 around fold 30 to the equivalent of approximately 1 thickness of the material, a step which is frequently encountered in asphalt composition roofing applications. Thus, the step beneath the portion 13 at fold line 30 is no more than normally encountered in the prior art.
When a roll of asphalt composition material 36 inches wide is used, the base 20' may be constructed having only a single fold made about fold line 30' as shown in FIG. 4. Strip 22' of adhesive would thereby be placed on the lower surface 11' near the center cut line 18' and would serve the same function as strip 22 of base 20.
As shown in FIG. 6, the individual tabs 40 are separated from the sheet shown in FIG. 5 along the center cut line 48 and the dashed lines between adjacent tabs, and a typical tab 40 has been folded about crease line 52, with the lower smooth side of first portion 45 lying flat against the lower smooth side of second portion 47. The folding of tab 40 may either be done at the factory or at the installation site, though folding at the installation is preferred, as it makes manufacture and packaging easier, and any splitting if folded cold is of little consequence because of the plastic stripes, i.e., plastic tape 54 acts as a hinge between the first and third portions and prevents the parts from separating along the fold line 52. Note from FIG. 5 that second portion 47 has a width slightly less than the width of first portion 45 and is offset inwardly from the sides of first portion 45 to produce an enhanced shadow effect which increases and emphasizes the depth of the roof covering system.
During installation, the bases 20 are laid edge to edge across the roof in a single course and, as shown in FIG. 7, the tabs 40 are inserted into bases 20 and nailed to provide one course of the roof covering system of the present invention. End 50 of each tab 40 is inserted into the fold created along line 30 of a corresponding base 20. The granule free region 26 of base 20 and strip 51 of each tab permits easy insertion of end 50 while minimizing the bulging which would otherwise occur at the fold due to granule buildup. Portion 47 of folded tab 40 is secured to the underlying granular surface of base 20 by the asphalt strip 58 which adheres to the base when warmed by the sun. The end 50 of first portion 45 is secured to the granule free area 26 of third portion 17 of base 20 and to the roof by a nail 60 passing through the end 50 and third portion 17 into the underlying sheathing of the roof. In this manner, the nail will not be visible, even before the next course is applied. However, the nail may also be installed so that it goes through the entire folded base and still provide double coverage in the finished roof as a result of the next course. Obviously, a number of tabs 40 of varying width may be positioned and secured to base 20 to create a more natural looking appearance, with a tab always being positioned over the region of abutment of two adjacent bases to provide a water barrier at that location.
As shown in FIG. 8, once the first course 80 of the roof covering system has been placed upon the roof, a second course 82 will be laid, with the lower edge of the third portion 17' of a second base 20' aligned with fold line 24 of the first course of bases. Thus, adhesive strips 22 on the first course will soften when warmed by the sun and adhere to the underside of the third portion 17' of the second course. This will prevent the bottom edge 32 of third portion 17' from lifting in heavy winds. A small section of a roof having several rows installed is illustrated in FIG. 8.
The description of the roof covering system thus far clearly illustrates the suitability of the roof covering system for installation on a flat roofing surface such as a layer of plywood. However, the same roof covering system is easily adaptable for installation over an existing thick shake roof by utilizing a spacer 90 as illustrated in FIG. 9 and discussed below.
An edge 74 of a pre-existing shake 70 presents a discontinuity in the surface over which the roof covering system is to be installed. The height of the discontinuity is substantially greater than that which can be readily accommodated solely by the base 20 and tabs 40 combined. However, by placing a spacer 90 at the foundation 73 of the edge 74, the effective height of the discontinuity can be reduced as desired. The spacer may be made of a piece of folded apshalt composition material, a long strip of thin wood molding or any other material having a thickness sufficient to raise base 20 to approach or even be flush with bottom edge 74. In the preferred embodiment, spacer 90 is an asphalt composition material folded about a first fold line 96 to form layers 92 and 94, and layer 94 folded about a second fold line 100 to form a third layer 98. The result is a thickened end 102 comprising layers 92, 94 and 98. The thickened end 102 is positioned to abut the edge 74 of a course of shake 70. Therefore, a base 20 is positioned atop the spacer 90 so that the first portion 13 of the base 20 will be approximately flush with the top 75 of edge 74. While normally the spacer will be temporarily attached to the roof, nails 60, driven through end 50 of tab 40, third portion 17 of base 20 and spacer 90 finally secures the roof covering system to the wood shake and the sheathing therebeneath. The process is then repeated until the roof is covered. In wood shingle reroofing, a spacer generally would not be required.
Now referring to FIG. 10, the installation of the roof covering system of the present invention using an alternate embodiment base to provide coverage over an existing wood shake roof without requiring a spacer as in FIG. 9 may be seen. in this embodiment, a typical base generally indicated by the numeral 120 has a lower panel or region 122, the function of which is the same as in the earlier embodiments. However, rather than merely having the Z shape fold as in the primary embodiment, each base 120 of FIG. 10 has an additional fold 124 so that the upper edge region of each base 120 overlies the multiple thickness region by the Z shape fold thereunder. This additional fold serves two purposes. First, the additional fold provides one additional thickness of asphalt composition material in the folded region to provide an additional thickness in the folded stack to better match the thickness of the thick wood shake 70. In addition, this final fold prevents the top edge region of each base from overlying the lower edge of the next shake thereabove (such overlying may be seen in FIG. 9). The net result is that the folded stack will closely approximate the thickness of typical thick wood shake so that no separate spacer is required with this embodiment. Aside from the bases themselves of course, the roof may be finished by the insertion in the usual manner of tabs 40.
There has been disclosed and described herein a roof covering system which utilizes lightweight and relatively inexpensive asphalt composition material to achieve a roofing product giving the appearance of substantial depth and texture to the roof. No part of the roof covering system is ever folded to more than three thicknesses, thus providing easy manipulation and cutting of the pieces. In areas where cutting of the multiple thicknesses is necessary, such as in the valleys, the system can easily be unfolded before cutting so that cutting of only one thickness is required.
In certain instances it may be desired to partially or totally eliminate the tabs to provide a low cost, high quality roof covering system. By way of example, one might desire to use the tabs with the roofing system hereinbefore described on the front facing portion of a house roof to provide maximum decorative effect while desiring a compatible though minimum cost covering on the rearward facing portion of the roof because of its lack of visibility, or because the appearance of the rearward facing portion of the roof will be less than ideal anyway because of roof mounted air conditioners, vents, solar collectors, etc. In still other instances it may be desired to provide a decorative roof on a home and thus use the tabs as hereinbefore described, but to provide a somewhat less decorative yet visually compatible and highly utilitarian covering on nearby detached buildings such as implement sheds, barns, garages and the like. In such instances, the bases of the present invention may be used without the tabs to provide the desired covering, as illustrated in FIGS. 10 and 11 and as hereafter described.
As shown in FIGS. 1 and 2, but not before described, each of the bases have a slit 110 extending from the center cut line 18 to the fold line 30 parallel to and approximately 4 inches in from the edge of the base. In the installation herein before described using the tabs in conjunction with the bases, the bases are folded as described without regard to the presence of the slits 110 therein. However, when using the bases without the tabs for a high quality yet low cost roof covering, the main portion of the base is folded as was illustrated with respect to FIG. 3, but the approximately 4 inch tab 112 is left unfolded as shown in FIG. 11. As illustrated in FIG. 12, the first base is then laid starting at the lower left corner of the roof, preferably by nailing through the base under the top flap of the fold so that that flap together with the lower portion of the base on the next course will provide double coverage. Then the next base for the same course is placed adjacent but overlapping the tab 112 of the first installed base so that the left edge 114 of the folded region of the second base substantially abuts the right edge 116 of the folded region of the first base. In this manner, a significant overlap of adjacent bases in a course is achieved to provide the desired water barrier in that region. The laying of the roof of course proceeds left to right and upward on a course to course basis until the roof is complete, the next course being laid so that the lower edge of each base extends slightly over the folded region of the course therebelow to provide a pronounced and attractive shadow line for each course. Each course, of course, is preferably staggered with respect to the course immediately therebelow (as is preferably done with the previously described embodiment) to provide a continuous coverage over the region of abutment of the sides of the folded region 114 and 116 of adjacent bases. The net result is a highly functional, low cost roof of perhaps reduced aesthetic character, though still quite attractive as a result of the pronounced horizontal shadow lines in comparison to the very flat appearance of typical prior art low cost asphalt composition roofing installations.
In the preferred embodiments described herein, the bases are cut in lengths of approximately 40 inches, but not folded at the mill so that they may be easily stacked flat for shipment. It should be recognized however, that the bases may be formed but not cut to length at the factory, but instead shipped in a roll so that the bases may be rolled out across a roof for further ease in installation. Care must be taken however, to avoid what is referred to "fish mouths", particularly when installed in cool weather, as particularly the more tightly rolled portions of a roll will not want to readiy lie flat on the roof when first unrolled. Generally speaking however, this problem may be overcome by unrolling the rolls on the roof while cutting the bases in substantial lengths, such as by way of example, ten foot lengths or even full roof widths, and allowing the unrolled material to sit for a day or so prior to installation. In such a case, of course, one would normally not use the tabs as illustrated in FIGS. 11 and 12 but rather use the embodiment of FIG. 1 without the tab slits.
While the invention has been described with particular reference to the embodiments illustrated in FIGS. 1 through 11, the figures and discussion are intended as illustrative of the invention and should not be interpreted as limitations upon the invention. It should be understood that many changes in configuration and substitutions of material may be made by one of ordinary skill in the art without departing from the spirit and scope of the invention as set forth in the appended claims.
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|U.S. Classification||52/521, 52/554, 52/540, 52/545|
|Cooperative Classification||E04D2001/005, E04D1/26|
|Jan 15, 1991||REMI||Maintenance fee reminder mailed|
|Jun 16, 1991||LAPS||Lapse for failure to pay maintenance fees|
|Aug 27, 1991||FP||Expired due to failure to pay maintenance fee|
Effective date: 19910616